The Hanging Church (El Muallaqa, Sitt Mariam, St Mary) derives its name from its location on top of the southern tower gate of the old Babylon fortress (in Old, or Coptic Cairo) with its nave suspended above the passage (Muallaqa translates to 'suspended'). It is the most famous Coptic Christian church in Cairo, as well as the first built in Basilcan style (possibly). It was probably built during the patriarchate of Isaac (690-92), though an earlier church building may have existed elsewhere dating as earlier as the 3rd or 4th century. However, the earliest mention of the church was a statement in the biography of the patriarch Joseph (831-49), when the governor of Egypt visited the establishment. The church was largely rebuilt during by the patriarch Abraham (975-78) and has seen many other restorations. Source: http://touregypt.net/featurestories/hangingchurch.htm